The present invention relates to a method for manufacturing an intelligent current distribution system for vehicles, in which method a current distribution cable is fitted with intelligent connecting sockets provided with output-connectors for supplying current to actuators to be connected to the system and switches for distributing current to the output connectors, as well as control electronics for controlling the switches on the basis of control commands received from a message communication bus of the cable or an input connector of the socket, the control electronics of each socket being provided with basic program for running sets of operation control instructions to perform various functions determined by the control commands.
The invention relates also to an intelligent current distribution system for vehicles, said system comprising:
a current distribution cable provided with one or more current conductors
at least one message communication bus
intelligent sockets, which are connected to the current conductor and to the message communication bus and which are provided with control electronics controlling operation of the socket and containing operating instructions specific for each socket for distributing current to actuators connected to the socket by way of controllable switches in response to control commands received from the message communication bus or from an input-connector of the socket, as well as operation control instructions for transmitting malfunction or control messages to the message communication bus.
This type of current distribution systems are prior known e.g. from publications WO 93/10951, WO 95/15594, EP-564943, and WO 97102965.
A weakness in these prior known systems is that too much intelligence required for control messages of functions is concentrated in the central unit of the system, whereby the communication becomes congested and the system is impaired in terms of its operating reliability. In order to reduce this drawback there has been proposed in European patent application EP-0 791 506 A2 to use highly intelligent node controllers under control of a central controller which sends a single command addressed to the proper intelligent node which in turn is provided with individual operation instructions for controlling the load connected to the node. One of the node controllers may be employed as a central controller. Because of need of the central controller there is still considerable reciprocating traffic between every node and the central controller which has to transmit every single command, query its performance and receive any condition messages from the nodes. Addressing the commands with node specific addresses provides an additional burden to data transmission because many of the commands or control messages are planned to be recognized or identified by several nodes.
One of the most serious defects of this prior art system is the lack of universal productability of the sockets because each socket has an individual assortment of operation control instructions. The specification of EP0 791 506 A2 does not propose any solution to avoid xe2x80x9ctaylor made xe2x80x9d production in order to provide each node with node specific instructions.
This is a serious shortcoming in all the prior known systems, wherein various optional applications of the system (such as various vehicle types or modifications even within a single vehicle type) cannot be flexibly manufactured on an automated line. The fluctuation in the level of loads and accessories in various models of even a single make of automobile causes considerable fluctuation in functions that the sockets are required to have. When applying the system to various makes of automobiles and various types of vehicles, the number of various optional embodiments becomes very large indeed. It is obvious that the manufacturing of various optional embodiments on an automated line becomes problematic, if the intelligence is decentralized in such a manner that the sockets are provided with individual intelligence as required by the operating demands of various loads or actuators connected therewith.
An object of the invention is to solve the above problem and to provide a current distribution system, which has a universal applicability and which nevertheless can be manufactured in a flexible manner on an automated line. Another object of the invention is to provide a method for manufacturing such a system with high automation level.
This object is achieved according to the invention by means of a method as set forth in the annexed claim I and by means of a system as set forth in claim 2.